Neumann M 147 Tube

Cardioid Tube Condenser Microphone

The mic’s “Operating Instructions” document, and some early reviews, refer to the capsule as an M7. This appears to be a misprint. The capsule pictured on Neumann’s website is not an M7; further, as far back as the mic’s announcement in 1999, the capsule has been referred to as a K47.

The K47 has dual diaphragms, but the rear diaphragm is not wired into the mic circuitry. The mic has a fixed Cardioid pickup pattern.

Martin Schneider

The standard K47/49 … [is] Cardioid somewhere below 1kHz, super/hypercardioid the higher you go. Thus, the M147 has the polar pattern of a U47 or U47fet, [a] tendency towards super/hypercardioid, as there’s no polarisation voltage on the rear [diaphragm].

Neumann’s current production K47 differs from vintage editions in at least one respect: the tensioning rings are made of nylon (plastic), rather than brass. In all cases, the capsule has dual diaphragms and a single (shared) backplate.

The tube in the amplifier circuit is used for impedance conversion. According to SoundOnSound, it is soldered to the circuit board.

The mic’s output is transformerless, which helps keep the mic’s self-noise to a very low 12dBA.

The capsule and amplifier circuit are separately shockmounted within the microphone body, to reduce handling and mechanical noise. The mic is compatible with, but does not include Neumann’s EA 1 elastic shockmount.

The M 147 Tube ships with a dual-voltage power supply, a power cable, a swivel mount, and an aluminum flight case.

SoundOnSound, 2000

The polar pattern is claimed to be a cardioid, but I found that it performed much more like a hypercardioid, particularly in the mid- and high-frequency regions…

[R]ecording spoken and singing voices (both male and female) with the mic distanced by around 18 inches produced a clean, articulate sound. Working closer… it gave a richer, warmer and more ‘ballsy’ sound…

[A] decent pop-screen is a necessity when using the mic for close recording.

The mic was initially launched at the Winter NAMM show in 1999, at a retail price of US $1995.